公开(公告)号：US09571775B1

公开(公告)日：2017-02-14

申请号：US14942622

申请日：2015-11-16

Applicant: OMNIVISION TECHNOLOGIES, INC.

Inventor： Liang Zuo ,  Zhihao Xu ,  Bi Yuan ,  Liping Deng ,  Yuxin Wang

IPC: H04N5/335 ,  H04N3/14 ,  H04N5/378 ,  H04N5/369 ,  H04N5/376 ,  H04N5/225

CPC classification number: H04N5/378 ,  H04N5/3698

Abstract: A ramp generator for use in readout circuitry includes an integrator coupled to receive a ramp generator input reference signal to generate a reference ramp signal coupled to be received by an analog to digital converter. A power supply compensation circuit that is coupled to generate the ramp generator input reference signal includes a delay circuit including a variable resistor and a filter capacitor coupled to receive a power supply signal. The variable resistor is tuned to match a delay ripple from the power supply to a bitline output. A capacitive voltage divider is coupled to the delay circuit to generate the ramp generator input reference signal. The capacitive voltage divider includes a first variable capacitor coupled to a second variable capacitor that are tuned to provide a capacitance ratio that matches a coupling ratio from the power supply to the bitline output.

Abstract translation: 用于读出电路的斜坡发生器包括一个积分器，该积分器被耦合以接收斜坡发生器输入参考信号，以产生耦合以由模数转换器接收的参考斜坡信号。 耦合以产生斜坡发生器输入参考信号的电源补偿电路包括延迟电路，该延迟电路包括耦合以接收电源信号的可变电阻器和滤波电容器。 调整可变电阻以匹配从电源到位线输出的延迟纹波。 电容分压器耦合到延迟电路以产生斜坡发生器输入参考信号。 电容分压器包括耦合到第二可变电容器的第一可变电容器，其被调谐以提供与从电源到位线输出的耦合比匹配的电容比。